Comprehensive Identification of Cell Cycle regulated Gen：细胞周期调控创综合识别.ppt

Comprehensive Identification of Cell Cycle-regulated Genes of the Yeast Saccharomyces cerevisiae by Microarray Hybridization Spellman et al. Questions What genes are cell cycle regulated? What genes are controlled by cell cycle regulators Cln3p and Clb2p? Are these cell cycle genes regulated by the same transcription factors? Cell Cycle Why is it important to study the cell cycle? Cancer Development Aging Microbes – environment, disease (prokaryotes don’t have a “cell cycle” like eukaryotes) Approach Genomics Three different synchronization methods α factor arrest cdc15 temperature-sensitive mutant Elutriation Induced expression of Cln3p and Clb2p Elutriation Induced expression of Cln3p and Clb2p DNA sequence analysis What genes are cell cycle regulated? Three independent synchronization methods. Took cell samples over two cell cycles. Data analysis was carried out in two different ways Phasing Clustering Phasing vs Clustering Major clusters G1 clusters CLN2 cluster – genes involved in DNA replication Y’ cluster – Y’ elements located in the telomeres Cluster of 92 genes involved with cell wall synthesis S and M clusters Histone Cluster MET cluster – methionine biosynthesis CLB2 cluster – genes involved in mitosis M/G1 Clusters MCM cluster – genes involved in DNA replication SIC1 cluster – genes that peak at the M/G1 boundary MAT cluster – genes that are MATα specific Induction of Cln3p and Clb2p 116 cell cycle regulated genes are induced by Cln3p and repressed by Clb2p 53 genes that are not cell cycle regulated respond to Cln3p or Clb2p Large overlap of genes regulated by these transcription factors DNA binding sites Conclusions 800 genes were found to be cell cycle regulated There are ~ 500 genes that are regulated by know transcription factors That leaves ~ 300 cell cycle genes whose regulation mechanism is unknown * *